Unit 1 - Chemical changes and structure

Question 1

What are the ‘Metallic Elements’?

Answer 1

Li, Be, Na, Mg, Al, K and Ca

Question 2

What are the ‘Covalent Molecular Elements’?

Answer 2

H2, N2, O2, F2, Cl2, P4, S8 and C40

Question 3

What are the ‘Covalent Network Elements’?

Answer 3

Boron, Diamond, Graphite and Si

Question 4

What are the ‘Monatomic’ elements?

Answer 4

Noble gases

Question 5

Define, ‘Covalent Radius’?

Answer 5

The measure of the size of an atom

Question 6

Explain the trend of the ‘Covalent Radius’ across periods?

Answer 6

The covalent radius decreases as the number of protons increases, the greater nucleus charge results in a stronger pull on the electrons

Question 7

Explain the trend of the ‘Covalent Radius’ down groups?

Answer 7

The covalent radius increases as the electron shells increases, the outer electrons are further from the nucleus which results in a shielding effect

Question 8

Define, ‘Ionisation Energy’?

Answer 8

The act of removing electron(s), which requires energy and is an endothermic process

Question 9

Explain the trend of the ‘Ionisation Energy’ across periods?

Answer 9

The first I.E increases due to an increase in nuclear charge and outer electrons are more strongly attracted to the nucleus making them harder to remove

Question 10

Explain the trend of the ‘Ionisation Energy’ down groups?

Answer 10

The first I.E decreases due to there being more occupied shells and more inner electrons cause a shielding effect making the electrons easier to use

Question 11

Define, ‘Electronegativity’?

Answer 11

A measure of the attraction an atom involved in a bond has for the electrons in the bond

Question 12

Explain the trend of the ‘Electronegativity’ across periods?

Answer 12

There is an increase due to an increase in nuclear charge and this causes the bonded electrons to be more attracted to the nucleus

Question 13

Explain the trend of the ‘Electronegativity’ down groups?

Answer 13

There is an decrease due to an increase in the number of occupied electron shells causing the bonding electrons to be less attracted the positive nuclear

Question 14

Define, ‘Ionic Bonding’?

Answer 14

The electrostatic attraction between positive and negative ions

Question 15

Define, ‘Covalent Bonding’?

Answer 15

The attraction between two positive nuclei and their common attraction for a shared pair of electrons

Question 16

Define, ‘Pure Covalent Bond’?

Answer 16

Where electrons are shared equally between the atoms because the atom’s electronegativity is equal

Question 17

Define, ‘Polar Covalent Bond’?

Answer 17

Formed when the attraction of atoms for a pair of binding electrons that are different

Question 18

“______ difference in electronegativity gives more ionic character”

Answer 18

Bigger difference in electronegativity gives more ionic character

Question 19

What do polar molecules contain?

Answer 19

They contain polar bonds, and have a shape that gives a clear delta negative and positive

Question 20

Define, ‘Intramolecular’?

Answer 20

Within molecules

Question 21

Define, ‘Intermolecular’?

Answer 21

Between molecules or atoms

Question 22

What are the three ‘Van Der Waal’s Forces’?

Answer 22

LDFs, Pd-Pd Interactions, and Hydrogen bonding

Question 23

Describe, ‘London Dispersion Forces’?

Answer 23

The weakest intermolecular forces, occurs between all atoms and molecules and are formed as a result of electrostatic attraction between temporary dipoles and induced dipoles that form because of the uneven distribution of electrons

Question 24

Describe, ‘Pd-Pd Interactions’?

Answer 24

Stronger than LDFs but weaker than Hydrogen bonding, occurs between polar covalent molecules, have higher melting point and boiling points due to the permanent dipoles attraction to each other

Question 25

Describe, ‘Hydrogen Bonding’?

Answer 25

The strongest Van Der Waal force, occurs when polar molecules contain a strongly electronegative element bonded to hydrogen (i.e nitrogen, oxygen and fluorine)

Question 26

What happens when you place a charged rod near a polar substance?

Answer 26

The polar substance will be attracted to the charged rod

Question 27

Define, ‘Viscosity’?

Answer 27

The measure of ‘thickness’ of a liquid; the thicker the liquid the more viscous it is, the stronger the intermolecular forces the higher the viscosity

Question 28

Describe, the density of ice and water?

Answer 28

The hydrogen bonding in water results in an expanded structure that causes the density of water (when ice) to be lower at low temperatures

Question 29

Define, ‘Soluble’?

Answer 29

When a gas or solid is able to dissolve in a liquid

Question 30

Define, ‘Miscible’?

Answer 30

A liquid that is able to mix/dissolve in another liquid

Question 31

Define, ‘Solvent’?

Answer 31

The liquid in which the substance dissolves in

Question 32

Why is water a useful solvent?

Answer 32

Its polarity can dissolve ionic substances due to its slightly negative ends of the water molecule that attract positive ions and the slightly positive ends attract negative ions

Question 33

Explain “Like dissolves Like”?

Answer 33

Non polar molecules are soluble in non polar solvents, ionic substances are soluble in polar solvents, and non polar substances are immiscible in polar solvents (vise versa)

Question 34

Define, ‘Oxidation’?

Answer 34

Where electrons are lost

Question 35

Define, ‘Reduction’?

Answer 35

Where electrons are gained

Question 36

Describe, ‘Oxidising Agents’?

Answer 36

A substance which accepts electrons in a reaction and it causes the other substance(s) in reaction to be oxidised

Question 37

Describe, ‘Reducing Agents’?

Answer 37

A substance which donates electrons in a reaction and it causes the other substance(s) in the reaction to be reduced

Question 38

Which substances make strong oxidising agents?

Answer 38

Substances with high electronegativity that will easily accept electrons

Question 39

Which substances make strong reducing agents?

Answer 39

Substances with low electronegativity that will easily donate electrons

Question 40

Define, ‘Spectator Ions’?

Answer 40

Ions that are present in REDOX reactions but do not take part in the reaction

Question 41

Explain what happens in Displacement reactions?

Answer 41

A more reactive metal that will displace a less reactive metal from a solution

Question 42

"The strongest _________ agents are at the bottom left-hand column of the electrochemical series"

Answer 42

"The strongest oxidising agents are at the bottom left-hand column of the electrochemical series"

Question 43

"The strongest ________ agents are at the top right-hand column of the electrochemical series"

Answer 43

"The strongest reducing agents are at the top right-hand column of the electrochemical series"

Question 44

Name Oxidising Agent(s)?

Answer 44

Hydrogen Peroxide, Potassium Permanganate, and Potassium Dichromate

Question 45

Name Reducing Agent(s)?

Answer 45

Carbon Monoxide and Chlorine

Question 46

Describe, ‘Potassium Permanganate’ and its uses?

Answer 46

An oxidising agent used to kill fungi, bacteria and inactive viruses, used in bleaches and to treat athlete’s foot

Question 47

Describe, ‘Hydrogen Peroxide’ and its uses?

Answer 47

An oxidising agent used to break down coloured compounds, used for bleach for in clothes and hair

Question 48

Describe, ‘Chlorine’ and its uses?

Answer 48

An reducing agent that kills bacteria by removing electrons from bacteria and when added to water it will breakdown to from hydrochloric acid